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We consider the problem of computing all subtree repeats in a given labeled ordered tree. We first transform the tree to a string representing its postfix notation, and then present an algorithm based on the bottom-up technique to solve it. The proposed algorithm consists of two phases: the preprocessing phase and the phase where all subtree repeats are computed. The linear time and space complexity of the proposed algorithm are important parts of its quality.  相似文献   
2.
Gastrin and cholecystokinin (CCK) are two major regulatory peptides synthesized by human gut and brain tissues as well as by selected tumors, in particular gastrin-producing neuroendocrine tumors. In the present study we have evaluated gastrin and CCK gene expression in a group of primary human tumors, including neuronal, renal, and myogenic stem cell tumors, using in situ hybridization techniques. In addition, CCK-A and CCK-B receptors were evaluated in the same group of tumors with receptor autoradiography. Most tumors had gastrin messenger ribonucleic acid (mRNA): 10 of 11 medulloblastomas, 5 of 5 central primitive neuroectodermal tumors, 11 of 11 Ewing sarcomas, 8 of 10 neuroblastomas, 4 of 4 Wilms' tumors, 5 of 5 rhabdomyosarcomas, and 10 of 10 leiomyosarcomas. CCK mRNA was restricted predominantly to Ewing sarcomas (9 of 11) and leiomyosarcomas (5 of 10). CCK-A and CCK-B receptors were not frequently found in these tumors, except for leiomyosarcomas. These data suggest that gastrin and CCK may play a previously unrecognized role in this group of human stem cell tumors. If the increased gastrin mRNA indeed translates into increased gastrin production, measurement of gastrinemia may have a diagnostic significance in the early detection of these tumors. As these two hormones have been reported to act as potent growth factors, they may be of pathophysiological relevance for patients with such stem cell tumors.  相似文献   
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Primary adenocarcinoma of sweat glands is a rare tumor; approximately 220 cases have been reported in the last 30 years. We reviewed the charts of patients with primary diagnosis of this tumor treated at the Mayo Clinic between 1935 and 1995. We included only cases with initial histology slides available for re-examination. Tumors were classified into five recognizable histologic patterns (solid, ductal, mucinous, microcystic adnexal, and adenocystic carcinoma) and graded by the Broder system. Statistical analysis consisted of Kaplan-Meier product limit method and Cox multiple regression test. In total, 55 patients were identified, and age ranged from 13 to 85 years (mean 59 years). Thirty-six patients (65 percent) presented to the Mayo Clinic for initial treatment; all except one had disease limited to the primary site. Microcystic adnexal carcinoma was the most frequent type, and more than 50 percent were grade 2 tumors. Among these 36 patients, 4 had some type of recurrence. Patients who developed metastasis had a high-grade tumor in the initial biopsy. Nineteen patients were referred with recurrence; 13 had local recurrence, 4 had regional diseases, and 2 had distant metastases. The histologic distribution showed 47 percent solid tumors, and 37 percent of them were grade 3. Multiple regression analysis did not show a difference in recurrence or survival when gender, age, tumor location, or histologic pattern was evaluated. In addition, there was no difference in the outcome between wide surgical resection and micrographic surgery. The only predictive factor for distant metastases and/or death (p < 0.003) was histologic grade. Overall 10-year survival rate was 86 and 60 percent for primary and referred patients, respectively. We conclude that histologic diagnosis of sweat gland carcinoma must be complemented by clinical examination to evaluate metastases. Clinical behavior depends on the histologic type of tumor, degree of differentiation, and clinical stage. On recurrence, the likelihood of further recurrences and mortality increases dramatically. Aggressive initial local ablation with tumor-free margins is recommended. In high-grade tumors, prophylactic regional lymph node dissection may further characterize tumor aggressiveness and may justify adjuvant radiotherapy as part of the primary treatment.  相似文献   
4.
BACKGROUND: Breath tests are currently used to qualitatively assess colonic fermentation; no quantitative estimations are available for healthy subjects. OBJECTIVE: This study describes a stable-isotope-dilution method to measure acetate production quantitatively from colonic bacterial fermentation. DESIGN: Six volunteers received a primed, constant, intravenous infusion of [1-13C]acetate at a rate of 1.01 +/- 0.04 micromol x kg(-1) x min(-1) for 7 h. They ingested 20 g pure lactulose after 1 h of the tracer infusion. Expired air and arterialized venous blood were sampled every 15 min. RESULTS: Before lactulose intake, the breath-hydrogen concentration was 7 +/- 2 ppm and the plasma acetate concentration and isotopic enrichment were 141 +/- 14 micromol/L and 14.8 +/- 1.4 moles percent excess, respectively. Whole-body acetate turnover was 6.0 +/- 0.7 micromol x kg(-1) x min(-1). After lactulose ingestion, maximum breath hydrogen and acetate concentrations reached 63 +/- 15 ppm (P = 0.004) and 313 +/- 25 micromol/L (P = 0.002), respectively, whereas [13C]acetate enrichment decreased to 9.9 +/- 1.3 moles percent excess (P = 0.03). Whole-body acetate turnover increased to 9.8 +/- 1.5 micromol x kg(-1) x min(-1) and later decreased almost to baseline values. Colonic lactulose fermentation yielded 140 +/- 12 mmol acetate over 6 h, representing 86% of the production based on stoichiometric equations. CONCLUSION: This new method provides a quantitative estimate of colonic carbohydrate fermentation via evaluation of acetate production.  相似文献   
5.
This study drew on data from the National Child Development Study to explore the role of father involvement and mother involvement at age 7 in father-child and mother-child relations at age 16, and the role of closeness to father and closeness to mother at age 16 in quality of relationship with partner at age 33. Closeness to mother was associated with closeness to father, intact family structure and academic motivation, and closeness to father with closeness to mother, early father involvement, less emotional and behavioral problems in adolescence, male gender and academic motivation. Closeness to father at age 16 was more strongly related to level of father involvement at age 7 for daughters than for sons and to closeness to mother for sons than for daughters. Marital adjustment at age 33 was related to good relationships with siblings, mother, and father at age 16; less current psychological distress; female gender; and educational attainment. (PsycINFO Database Record (c) 2010 APA, all rights reserved)  相似文献   
6.
Within the framework of achieving the European environmental targets towards climate change mitigation, as well as decreasing the fossil fuel dependence and its negative effects on global warming, renewable energy sources (RES) promotion has become a major issue of concern in most European Union (EU) countries. In the above context, most EU countries have endorsed initiatives to foster RES implementation development and inclusion in the energy mix, aiming to endeavor and further impel the benefits deriving from RES and harmonize to the EU Directive or Kyoto Protocol. Nevertheless, only few sporadic efforts have been examining countries and compare the requirements for promoting RES implementation that lack specific RES obligations or a framework set by the Kyoto Protocol or the EU Directive, and particular Balkans countries with great RES potential, such as BiH and Serbia. The main objective of this paper is to analyze the conditions and modalities for RES progress within the economic, political and institutional dimension, in these two neighboring countries located in the vicinity of EU Member States (MS), which appear to have a similar historical, political and economical background and an extensive RES potential. The analysis indicated that RES development in BiH seems to be a slow process, its institutional framework is partly established and further strengthening is required. In Serbia, the institutional framework is efficiently established, are in the process of developing new legislation to facilitate renewable energy development.  相似文献   
7.
There is limited research on the links between grandparenting and adolescents' well-being, especially from the perspective of the adolescents. The study examined whether grandparent involvement varied in two-parent biological, lone-parent, and step-families and whether this had a different contribution to the emotional and behavioral adjustment of adolescents across different family structures. The study is based on a sample of 1,515 secondary school students (ages 11-16 years) from England and Wales who completed a structured questionnaire. Findings of hierarchical regression analyses showed that among the whole sample, greater grandparent involvement was associated with fewer emotional problems (p  相似文献   
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